Conventionally, among organopolysiloxane compositions that are turned into rubbery elastic bodies when cured at room temperature, the so-called one-component type (one-component) room temperature-curable organopolysiloxane composition allowing curing reaction to progress when in contact with water in the air has been widely used as an elastic adhesive agent and coating material in the electrical/electronic industry or other industries, or as an architectural sealing material, for example. This is because there are required no cumbersome steps of weighing and mixing a base polymer, a cross-linking material, a catalyst or the like immediately before use, which causes no error in composition; and because an excellent adhesiveness to a wide range of base materials is usually exhibited even when no primer is employed. Such one-component type room temperature-curable organopolysiloxane composition is often categorized by a compound(s) released therefrom when coming into contact with water in the air, typical examples of which include organopolysiloxane compositions of a deacetic acid type, a deoximation type, a deamide type, a dehydroxylamine type, a deacetone type, and a dealcoholization type. Among these examples, an dealcoholization-type organopolysiloxane composition which is curable by releasing an alcohol(s) is particularly preferred and used, because it has little odor, does not corrode metals such as copper and iron, and exhibits an excellent self-adhesiveness (adhesiveness to various base materials after curing, when no primer is employed) and adhesion durability.
However, although a one-component dealcoholization-type organopolysiloxane composition has the above excellent properties during a short period of time after its production, the composition has a flaw(s) in its storage stability where, for example, the properties that are observed immediately after the production of the composition may be lost over time during storage, depending on the ingredients of the composition. Further, when stored under direct sunlight at the site of use, or when stored in a container while being transported, the storage environment is often a high temperature environment of a temperature greater than 50° C. Thus, there has been a problem that, for example, not only the properties that are observed immediately after production may be lost even after a relatively short-term storage, but curing failures may occur as well.
The one-component dealcoholization-type organopolysiloxane composition has long been proposed. Typical examples of such composition include a composition comprised of a hydroxyl group end-capped organopolysiloxane, alkoxysilane and a titanium compound, as disclosed in Japanese Examined Patent Application Publication No. Sho 39-27643 (Patent document 1). Further, JP-A-Sho 55-43119 (Patent document 2) discloses a composition comprised of an organopolysiloxane having an alkoxysiloxy group at its end, alkoxysilane and alkoxytitanium. However, these compositions have exhibited a problem that, for example, when calcium carbonate is added to impart a favorable physical property to a sealing material, the storage stability of the compositions may be impaired in a way such that a desired property may not be achieved after a long-term storage, and/or the compositions may fail to cure after being stored in a high-temperature environment of a temperature higher than 50° C. Moreover, Japanese Examined Patent Application Publication No. Hei 7-39547 (Patent document 3) discloses a composition superior in storage stability in a sealed condition. However, this composition disclosed requires the use of a polymer prepared by modifying the end of an organopolysiloxane with an alkoxysilyl alkylene group. That is, due to the preparation of such polymer, this composition has a problem of industrially incurring a higher cost. In addition, Japanese Patent No. 4775600 (Patent document 4) has recently proposed improving storage stability by adding a polyhydric alcohol fatty acid ester such as triacetin which is a typical example thereof. However, since these compounds have an insufficient compatibility with siloxanes, there exists a problem that these compounds may bleed out of a cured product after curing, and that the adhesiveness may thus be impaired.